Nodes in a phylogenetic tree represent:

Question

BlackTom AI · Accepted Answer

Question context: We’re looking at what nodes in a phylogenetic tree signify, with several candidate statements to evaluate.
Option 1: 'Genetic material from biological samples you collected.' This is not what nodes represent. Genetic material corresponds to the data you might sequence from tips or leaves, not the abstract points (nodes) that encode hypotheses about ancestry.
Option 2: 'Siblings of the tree tips.' Leaves (tips) have siblings, but the nodes themselves are not defined as the siblings of tips. Nodes are points on branches, representing ancestral relationships, not the immediate relatives at the tips.
Option 3: 'Different genes in the same organism or different individuals in the same species.' This confuses the concept of genes with the representation of ancestry. A tree node is about lineage history, not a particular gene or a collection of genes.
Option 4: 'An abstraction of a previous generation.' This captures the core idea: internal nodes represent hypothetical common ancestors from earlier generations, serving as abstractions in the reconstruction of evolutionary history.
Option 5: 'The direct ancestors of the tips.' This statement is tempting but imprecise. An internal node can correspond to a common ancestor shared by multiple tips, but not every internal node is a direct ancestor of a specific tip, and some nodes represent ancestral lineages that are not direct ancestors of all descendant tips. Therefore, describing nodes as simply 'the direct ancestors of the tips' is misleading.
Summary: After evaluating each option, the statement that best matches the meaning of a node is that it is 'an abstraction of a previous generation,' while the others mischaracterize what nodes represent in a phylogenetic tree.

Nodes in a phylogenetic tree represent:单项选择题

类似问题

In the following hypothetical tree, identify the sister node(s) of M.

There is more than one correct way to show relationships using a phylogenetic tree. Three of the four trees displayed below show the same relationship between species A, B, and C. Which tree shows a different relationship?

Using the tree below, which letter refers to the most recent common ancestor of green alga and moss?

Which species is closest to C based on the following phylogenetic tree?

Which of the following statements about rooted and unrooted phylogenetic trees is CORRECT?

Which one of the following statements about the following phylogenetic tree is correct?

According to this figure, chimpanzees are most closely related to ______ .

Which node represents the most recent common ancestor of organisms E and F?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单